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Reservoir (IL)

Isothermal liquid reservoir at constant or time-varying pressure

Since R2020a

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  • Reservoir (IL) block

Libraries:
Simscape / Foundation Library / Isothermal Liquid / Elements

Description

The Reservoir (IL) block represents an infinite reservoir of isothermal liquid. Use this block to set the boundary condition in an isothermal liquid network. The liquid in the reservoir can be at a constant pressure, either atmospheric or specified by a block parameter. You can also control the pressure inside the reservoir by using the physical signal input port P. Port A, an isothermal liquid conserving port, represents the reservoir inlet.

The block icon changes depending on the values of the Reservoir type and Reservoir pressure specification parameters.

Reservoir TypeReservoir Pressure SpecificationBlock Icon

Constant

Atmospheric pressure

Specified pressure

Controlled

Assumptions and Limitations

  • The volume of liquid inside the reservoir is assumed infinite. Therefore, the flow is assumed quasi-steady.

  • There is no flow resistance between port A and the reservoir interior.

Examples

Hydraulic Actuator with Analog Position Controller

Hydraulic Actuator with Analog Position Controller

How the Foundation library can be used to model systems that span electrical, mechanical and isothermal liquid domains. In the model, a hydraulic system implemented in the isothermal liquid domain controls the mechanical load position in response to a voltage reference demand. If the reference demand is zero, then the hydraulic actuator (and load) displacement is zero, and if the reference is +5 volts, then the displacement is 100 mm.

Ports

Input

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Physical signal port that provides the reservoir pressure control signal. The signal saturates when its value drops below the minimum valid pressure specified by the Isothermal Liquid Properties (IL) block connected to the circuit.

Dependencies

This port is visible only if you set the Reservoir type parameter to Controlled.

Conserving

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Isothermal liquid conserving port associated with the reservoir inlet.

Parameters

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Select whether the reservoir pressure can change during simulation:

  • Constant — The reservoir pressure remains constant during simulation. Port P is hidden.

  • Controlled — The input physical signal at port P specifies the reservoir pressure, which can vary during simulation.

Specification method for the reservoir pressure:

  • Atmospheric pressure — Use the atmospheric pressure specified by the Isothermal Liquid Properties (IL) block connected to the circuit.

  • Specified pressure — Specify a value by using the Reservoir pressure parameter.

Dependencies

Enabled when the Reservoir type parameter is set to Constant.

Desired pressure in the reservoir. This pressure remains constant during simulation. The specified pressure cannot be greater than the atmospheric pressure specified by the Isothermal Liquid Properties (IL) block connected to the circuit.

Dependencies

Enabled when the Reservoir pressure specification parameter is set to Specified pressure.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2020a

See Also

Topics